This invention relates to an expandable envelope construction.
As is known, envelopes have been constructed for a number of purposes, for example, for the mailing of letters, business correspondence, merchandise, such as CD carriers and the like through the mails and thus need to conform to specified size requirements. Envelopes have also been constructed for use in the filing of various types of materials and in some cases, have been constructed to expand in order to increase the capacity of the envelope. Generally, these envelopes have been glued and finished by hand. In addition, these envelopes have had an internal gusset construction which restricts the insertion of papers.
Typically, the degree to which an expandable envelope can be expanded has been limited. Further, should an envelope become overstuffed, the edges tend to become rounded with the appearance of the envelope becoming less than aesthetically pleasing.
U.S. Design Pat. No. 405,823 illustrates an envelope for commercial literature which has tapered edges on three sides and an enlarged pocket. In addition, a pair of flaps are illustrated, with at least one flap providing for closure of the pocket.
An expandable envelope construction is also known for shipping CDs wherein the front and back are each provided with score lines spaced inwardly of the edges in order to permit the envelope to expand upon the insertion of a CD holder while retaining a flat appearance. The envelope is made from a blank having a rectangular panel to form the face of the envelope and from which trapezoidal shaped flaps extend from two sides, a second panel extends from the bottom to eventually form part of the back of the envelope and a closure flap extends from the top. The back panel folds over the face panel as well as over the side flaps to form a pocket. In addition, the back panel has a trapezoidal shaped section with edges which face the edges of the side flaps when the envelope is empty and flat. The closure flap has similar edges to face the side flaps at the top corners. However, when the envelope is stuffed, the corners of the envelope tend to open. As a result not only arc the contents not completely sealed from the outside environment but also the appearance of the back of the envelope is less than desirable.
Accordingly, it is an object of this invention to provide an aesthetically pleasing envelope construction which is of an expandable nature.
It is another object of the invention to provide an expandable envelope construction which can be readily fabricated on automated equipment.
It is another object of the invention to provide a flat expandable envelope construction which can be filled to capacity while retaining the contents in a fully sealed condition while retaining a flat appearance.
It is another object of the invention to provide an expandable envelope that may be opened to remove the contents and re-closed after refilling with all or some of the contents.
It is another object of the invention to provide an expandable envelope of corrugated construction which can be used as a re-useable envelope.
It is another object of the invention to provide an expandable envelope which can be mechanically stuffed and closed.
Briefly, the invention is directed to an expandable envelope construction comprising a rectangular front panel, a pair of side flaps at opposite sides of the front panel for folding over the front panel along a vertical fold line, a back panel disposed over the front panel to form a pocket and a closure flap for folding over the back panel to close the pocket. In addition, at least the back panel and the flaps are provided with score lines to allow for expansion of the pocket while maintaining the flat appearance of the envelope.
In accordance with the invention, each side flap includes a first section which extends from a respective vertical fold line and a reduced second section which extends from the first section. In addition, the back panel is secured to the second section of each of the folded-over side flaps between the score lines by means of an adhesive on the flaps to form a pocket. The back panel has a trapezoidal section extending from the horizontal fold line in overlying unsecured relation to the first section of each side flap. Likewise, the closure flap extends over the first section of each flap in an unsecured manner. Thus, upon insertion of materials into the pocket, the panels are expandable from each other to enlarge the thickness of the pocket while the corners of the pocket also expand while being maintained in a sealed condition.
In one embodiment, the front panel is also provided with score lines along each edge so as to be capable of expanding in the same manner as the back panel. This envelope construction is such that, upon insertion of materials into the pocket, the front and back faces expand from each other while the two sides and the bottom of the envelope construction collapse inwardly about the respective pairs of score lines adjacent the fold lines on each edge of the envelope construction. For example, for an envelope construction intended to have a thickness capacity of one-half inch, the score lines are spaced one-half inch from the adjacent fold line. The envelope may then be expanded from an empty flat condition to one in which the pocket is one-half inch thick while retaining a flat appearance.
After materials have been introduced into the pocket of the envelope construction, the closure flap is folded over the back face to close the pocket. In one embodiment, the closure flap is provided with means for securing the closure flap to the back panel. For example, the means for securing the closure flap may include an adhesive strip along an inside edge of the closure flap and a removable barrier strip over the adhesive strip. Upon removal of the barrier strip, the adhesive strip is exposed for sealing purposes.
The closure flap may also include a horizontally disposed removable strip which, upon removal, unseals the remainder of the closure flap from the back panel of the envelope construction so that the contents of the pocket may be removed. In order to facilitate removal of the strip, a tab is provided at one end of the strip to extend beyond the closure flap for manual or mechanical gripping. For purposes of mechanical stuffing and closing of the envelope construction, the tab may be disposed on one side or the other of the envelope construction. Further, the removable strip may terminate short of one edge of the closure flap.
In another embodiment, the envelope construction may have means on the closure flap between the removable strip and the front panel for reclosing the closure flap over the back panel. Such a reclosing means may be in the form of a ribbon for wrapping about the panels or may be in the form of an adhesive strip which is covered over by a releasable barrier strip or in the form of Velcro strips or elements which cooperate with Velcro elements on the back panel.
The envelope construction may be made in various sizes and materials in order to accommodate various materials to be retained in the pocket. For example, the envelope construction may be sized to receive letter size sheets of paper, magazines, catalogs and the like. The envelope construction may also be made of smaller sizes, for example, to receive and ship CD carriers, and of larger sizes, for example, to receive three-ring binders.
In one embodiment, the envelope is made with an overall size of 10 inches by 7 inches with expansion score lines on only the back panel, side flap and closure flap. In this embodiment, the front panel is smooth and uninterrupted with score lines. This is so that the mailing side of the envelope construction does not show scores.
In another embodiment, the envelope construction may have a size of 10xc2xd inches by 7xc2xd inches with the front panel having a window for viewing of an address on the materials within the pocket. Typically, a glassine patch would be secured to an inside surface the front panel over the window to protect the contents of the pocket. Such an envelope may be used to include a packet of materials with a wrap-around letter with an address on the letter showing through the window. In this embodiment, the material of the envelope construction may be made of an E or F fluted corrugated material to add strength where needed.
Depending on the capacity required of an envelope construction, the size of the envelope and the dimensions of the scores may vary.
In still another embodiment, the envelope construction may be made of embossed material. Such a construction is particularly of interest when containing folders or other envelopes of similar embossed construction. For example, the envelope construction may have dimensions of 13 inches by 10xc2xc inches so as to be matched for insertion of a 12 inch by 9xc2xd inch folder. Such a dimensional relationship allows the folder to be mailed without being damaged.
In still another embodiment, the back panel may be provided with a horizontally disposed slot while the closure flap is made of a length to be inserted into the slot upon closing of the pocket. In this embodiment, the closure flap is not sealed to the back panel but is instead removably held in place. Such an embodiment is particularly useful as a folder.
In still another embodiment, the envelope construction may be sized for mechanical or automatic insertion equipment. For example, a size of 11xe2x85x9e inches by 9xe2x85x9c inches is particularly suited to such equipment. In such an embodiment, the equipment would insert 8xc2xd inch by 11 inch booklets or pamphlets up to xe2x85x9c inch thickness into the pockets of the envelope constructions. The size of the envelope and the thickness for insertion of materials may vary by being bigger or smaller depending upon the customer""s needs.
Adhesive may also be applied mechanically to seal the envelope construction. In this case, the tab on the removable strip in the closure flap may project from one side or the other side of the closure flap to enable an inserting arm that lifts the flap not to jam as the envelope construction passes through the mechanical device. Further, with this embodiment, the expansion scores may be double scored to allow for easier opening of the closure flap for mechanical insertions.
In still another embodiment, the envelope construction may be sized and made of materials suitable for use as a mailing container. For example, an envelope construction having dimensions of 14⅝ inches by 13xe2x85x9c inches may be used to receive a 1 inch thick three-ring binder. In this case, the paper used would be a F-flute corrugated material or an E-flute corrugated material or similar stiff material.
In still another embodiment, the envelope construction may be made for reuse, as a carrying case. For example, cooperating Velcro elements may be placed on the closure flap and the back panel for releasably securing the closure flap to the back panel. In addition, each of the front panel and closure flap may be provided with a hinged blank which can be punched out and folded back to form a handle.
In another embodiment, the expandable envelope construction may be made with a rectangular front panel having horizontal and vertical score lines as above with angularly disposed score lines extending to a respective corner of the panel. In addition, a pair of flaps are disposed at opposite sides of the front panel with each flap being folded over along a vertical fold line. In this embodiment, a back panel extends from and is folded over the front panel along a horizontal fold line and is secured to the flaps to define a pocket. The back panel is also provided with horizontal and vertical score lines as well as angularly disposed score lines extending from the intersection of a horizontal and vertical score line to a corner of the back panel.
In this embodiment, the side flaps need extend only a short distance inwardly of the front panel thereby terminating short of an adjacent vertical score line on the back panel as the front and back panels are secured at the corners without any gaps there between.
The envelope construction may be readily made from a single blank which can be pre-scored and provided with fold lines. In addition, the equipment for folding the blank may be of simple construction. For example, the equipment may be automated to have a folding station in which flaps on the sides of a panel of blank are folded over onto the panel, a gluing station in which adhesive is applied to the folded over flaps and a second folding station in which another panel of the blank is folded over and secured to onto the side flaps to form a pocket. A further station may be used to apply adhesive or another type of securing means to the closure flap.